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Run red-green-refactor in vertical slices, emphasizing behavior-first tests and harness quality gates.
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Based on SOC occupation classification
| name | tdd |
| description | Run red-green-refactor in vertical slices, emphasizing behavior-first tests and harness quality gates. |
Use test-driven development to deliver features/fixes in small behavior-focused increments.
Before coding:
Create one thin end-to-end test that proves a real path.
RED: write one failing behavior test
GREEN: write minimal code to pass
For each next behavior:
RED: next failing behavior test
GREEN: minimal implementation
Rules:
When all current tests are green:
Never refactor while red.
After meaningful changes, run:
bun run typecheck
bun run lint
bun test
If a sub-repo defines different commands, follow that sub-repo's AGENTS.md.
Use beads to track TDD slices:
bd create --type task --title "TDD slice: <behavior>" --description "<expected behavior and test scope>" --priority 2 --repo .
bd comments add <id> "worklog: red->green completed for <behavior>"
Bundled with this skill (self-contained — no external repos required):
The bundled deep-dive docs (tests.md, interface-design.md,
deep-modules.md, mocking.md, refactoring.md) are
vendored verbatim from the tdd skill in mattpocock/skills.
This SKILL.md is an Agent Forge adaptation of the same concepts (Beads tracking + harness quality
gates). Original work © 2026 Matt Pocock, MIT License:
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND.
Break a plan/PRD into independent vertical-slice Beads issues with explicit dependencies.
Synthesize current context into a PRD and file it as a Beads feature/epic issue.
Phase 2 of the Forge pipeline. Turn a research document into an implementation plan that is built around Beads issues and TDD. Reads plans/research/<slug>.md, designs the build, sets up red-green-refactor test strategy using the tdd skill, materializes a Beads epic/feature/tasks with dependencies and priorities, and defines demo/test checkpoints. Use when starting /forge-plan or the plan step of /forgemaster.
Fact-check an implementation plan against the real codebase and first-party documentation, flagging inaccuracies with what / why / evidence and a severity tier. Use when the user wants a plan reviewed or validated for accuracy, runs /review-plan, or wants a plan checked against real code before implementing. Accepts a Beads issue, a filesystem path, or a plan pasted into chat.
Phase 3 of the Forge pipeline. Execute the plan's Beads tasks with red-green-refactor TDD, committing per checkpoint and pausing at each natural stopping point so the user can run a live demo or test and see the work themselves. Use when starting /forge-implement or the implement step of /forgemaster.
Phase 1 of the Forge pipeline. Gather real context from the codebase, answer everything the code can answer through exploration, then grill the user one question at a time (with a recommended answer) for only what code cannot answer, and write a research document. Use when starting /forge-research or the research step of /forgemaster, or when the user wants a research-first investigation before planning a feature.